How odd these pirate games are. Actually, this is a homebrew port of Mortal Kombat Mythologies: Sub-Zero for Sega Mega Drive. It seems to be developed in the first part of 2000 by 台湾游戏公司 which is completely unknown nowdays. You've never heard of this game? So, now you do =)
It was barely known outside China and no-one seems to talk about it or even mentioning it, so people meet it only by either purchasing a pirate cartridge or watching someone playing it. Personally, I had a cartridge with all MK's ever released on Mega Drive.

There isn't much to say. It's a hallway side-scroller fighting where you walk around, fight a single opponent at once, collect items and look for the "exit". Sounds common, but it's a stiff and difficult game. The control is awful, less comfortable than in a normal MK game, and the enemies' behaviour is more unpredictable. Though an emulator fixes it, a hardware player will probably sick of it. It is also designed for a 3-button controller, so there isn't much a variety of actions you can perform.

Game objectives

SHA1: 5AD8F8AD871F8C2A4D669CAC6759090C

Emulator used: Bizhawk 2.3.0 (was Gens v11a)

Unofficial game

Takes damage to save time

Uses hardest difficulty

Major skip glitch

Final boss skip glitch

Genre: Action

Comments

There 3 types of rooms: with enemies, with traps (stage hazards), with nothing. You fight 1 enemy at the same time. After you kill him, the next one spawns outside the screen. If there are no more enemies to fight, you're able to quit the hallway.
The spawn depends on the players position. Enemy spawns on the left of the player if he is in the right (opposite to "left") part of the level and/or the camera isn't able to move right (there is still an area to prevent it). In all other cases, an enemy spawns on the right side, so I complete the same hallway faster if I go to the right.

The traps work ciclically. If the player touches them, he recieves damage and falls back. Also their hitboxes mismatch their sprites, so I sometimes don't catch a visual moment when Sub-Zero is supposed to stay untouched if I would go/jump on the Nth frame. I have to mention that I saved only 16 frames of taking damage.

Enemies

Drawing is such a hard process. It's much easier to copy the characters from MK3. There I fight colourful Kanos, Liu Kangs, Sonyas and Sindel. They perform the same move set as Sub-Zero, but there are some differences outside their skins.

Sonya/Sindel can launch fireballs and often attack you. After getting up, she always acts first: if you attack her in advance, she ignore it and counterattack you. Fortunately, you can deal damage with foot sweeps and knock her down before she is able to do anything.

Liu Kang can throw a boomerang. He is vulnerable to your attacks while getting up, so you may have less problems with him.

Kano can't throw his laser knives like in MK3, but he always acts first and you're not able to hit him while he is getting up.

Stage by stage comments

Stage 2

It has a huge map with many rooms and there are enemies in almost all of them. Normally, you should collect 3 keys and visit the major part of rooms, that would take about 12 minutes in total. 1st key opens the door to the 2nd one, 2nd key activates the elevator to the 3rd one, and 3rd key will finally bring to the exit.
I did a major shortcut with help of Sub-Zero's slide tackle move and took the 3rd key quickly, ignoring other 2 keys. The room can be crossed 3 slides , but 2 slides spend all my mana I had to wait until it restores. 2 slides would be enough, but I need 6 more pixels offset to do it with the additional help of a jump. A goblet with the potion restores your mana, like health, but it was not available for me.

Stage 4

This map is even bigger then Stage 2. There you should collect 3 emeralds and place them in certain places.
The whole map can be seen here. Hallways proportions are wrong, because I drew it for myself.
Nothing to add. This stage is boring even on Easy difficulty.

Fortunately, this stage is completed with the help a weird glitch that finishes the stage if Sub-Zero falls through the ground. The same trick was used to complete Streets of Rage 1.
I couldn't reproduce this glitch anywhere, but zoboner rescued the situation! I don't know how humble he is for real, but the world needs to know its heroes =)
He improved my TAS by 14 minutes. You're so helpful!

Other tricks and glitches

Corner hitting trick

There are invisible walls at both edges of any room that can be crossed only by CPU in order to get to the player. If you hit the enemy while he is crossing the whole, you slide back a lot. Sub-Zero's punching is the fastest strategy, so this trick can be used when the enemy has already crossed the inv. wall and has nowhere to slide back and you can punch him rapidly until he is dead.

Slide tackle shortcut

As mentioned above, it's possible to cross the room with no floor if you perform a slide move. The deal is, the game checks if Sub-Zero stands on the surface only he walks. So, you're able to slide from the edge of a platform without falling down. Also, you can jump off the air, but you should land on the real surface then.

Check point bypass

When you get an essentional item like a key, the game saves. It's a good sign for a player, but a bad - for TASer. If you die, you respawn on your last check point, not at the starting point, so you can't bypass any hallways that must be passed in order to get to the point B quickly. The only thing is, the game doesn't save if you collect a key while having zero health. It wuold be useful in Stage 3 when I take the square key, but quiting the hallway normally is faster than passing the opposite hallway where I would respawn.

Quick side changing

When an enemy spawns, he runs for a certain period of time towards the player. When you need to push the enemy to the opposite side, you can jump over him or make him walk into you if he is running. The last tactic is commonly used through the whole TAS.

Stage 4 skip

It's a weird glitch that finishes the stage if Sub-Zero falls through the ground. Normally, if Sub-Zero falls below the screen, he dies, but there is no any pits on this stage, so this function isn't invoked there. The true reason of such an odd game's behaviour is unknown for me, sorry.
To reproduce it, you have to use Sub-Zero's ground freeze attack on an enemy and then jump towards his/her body. If you catch the right moment, Sub-Zero will move down through the floor.

Other comments

In case someone is wondering how to perform these damn ice attacks, I'll tell you!

Ice throw

Press down and right (if you're faced to the right). Then hold Right at least for 1 frame. While holding Right, press B.
It has to be like that: \/>, >, >B.

Ice puddle

The same as above.
It has to be like that: <\/, <, <C.

Well, it's all over not. Useful RAM Watch addresses can be downloaded here in case someone will ever visit this (...) game.

Dimon12321: Description has been updated due to recent improvements and the emulator change.

fsvgm777: Replacing movie file with one done one a more accurate emulator and with a 254-frame net improvement (14 in-game seconds when disregarding emulation differences)

feos: Game name from the box and and cartridge varies, and neither can be called official, since it steals elements from existing games and the name there varies. So I'm using the name from the title screen, with some usual stylization we apply. That's unavoidable when the in-game title is this:

MK
5
MORTAL COMBAT
~SUB ZERO~

Notice that it's "C" in the full name, but "K" in the abbreviation. I think it's worth using the entire title here.

feos: While this game is not well known, I think it meets the Vault notability requirements for unlicensed games.

First of all, the very fact that a game from a newer console has been back-ported to an older one deserves some credit.

Second, there are still quite some matches on Google and YouTube, so Mortal Kombat aware people have seen or played this game.

Third, while it's honestly boring, it's not as terrible as Mortal Kombat ports to Dendy! It feels like a real game, just a low quality one. The music alone is so amusing compared to how it sounds in iconic 2D MK games, and it adds to the irony those games have when they're being violent.